Tuesday, September 02, 2014

Ever accidentally hit “Mute” on the TV while watching a movie? Suddenly what you’re seeing loses much of its impact. That’s because the audio, be in voices, music, or background sounds all play a part in creating the total atmosphere for the viewer. Movie theaters were quick to focus in on this, making sound an important part of the theater-goers overall experience.

For those watching at home, emulating the movie theaters means more than just having a big TV to look at; the audio being listened to must be enhanced also. So this gave rise to sound bars and multiple speaker setups that could take advantage of 5.1 sound: a front left and right speaker with a center channel between them, accompanied by two surround speakers (left and right) along with a subwoofer. Next came additional audio channels, for example, 7.1, which added more speakers to further enhance the audio.

But if the goal is to create an “atmosphere of sound” to engulf the viewer, then Dolby Atmos could very well be the answer. And you don’t have to go to a movie theater in order to experience it either — it’s coming to your home theater right now.

Dolby Atmos operates on the principle of control: the audio that’s being listened to isn’t a hodgepodge as its placement in “space” and how it “moves” around the audience is totally under the filmmaker’s control. So what you hear at home is the same as what you hear in the theater. To have this kind of control over the audio, multiple speakers need to be used, and these speakers need to be at various locations in the room — this includes placing them overhead. Independent speaker control means a layered effect that duplicates the audio reality of life in a dynamic and organic manner that is natural to the listener. This is due to Dolby Atmos behaving by looking at sound not as audio streams but as objects: so if a car horn is blaring, this sound is crafted so that it is heard as it would be in real life. On the technical side of things, Dolby Atmos automatically generates optimum soundtracks for movie theaters with 5.1/7.1-channel setups and scales up to the number of speakers available (up to 64 independent speaker outputs). This same technology plays its part where the home theater is concerned as Dolby Atmos looks at how many speakers are there so as to utilize them effectively.

Let’s set up a Dolby Atmos home theater. To begin, we don’t have to throw out our existing speakers — good — but we will have to augment them. So we have our 5.1 audio system which consists of front left and right speaker and a center channel. We also have a set of surround speakers to our left and right, and these are placed so as to be about even with our ears as we sit to watch (in general, surrounds can not be “ahead” of the listeners if they are to be effective). A subwoofer for deep bass sits in a corner.

But now comes more speakers. One way to do this is by installing speakers in the ceiling. It’s an efficient way to do this — requiring professionals of course to do the install. But it’s not the only way, which is good for apartment renters and those who aren’t allowed to treat their ceilings in an invasive manner. Sound can be “bounced” off the ceiling. There are Dolby Atmos-compatible speakers which can take the place of the front Left/Right speakers: they have front firing speakers as well as upward-firing speakers, all in the same cabinet. There are also Dolby Atmos-compatible speakers designed to be placed on top of the front L/R; these speakers are send their audio upwards only — having it reflected off the ceiling and then directed back down to those in the home theater.